2006 Vortec Max 4L80E swap

[Vortecmax2006]

Hi there guys new member here.

Have a 2006 GMC Sierra, vortec max 4wd truck. Came with a 4.10 gear and LQ9/4L70e from the factory.

 

has been a great truck for me so far, use it to tow my 8,000lb travel trailer fairly often.

 

my second gear has started to slip and rather than replace it with another 70 I have bought a complete parts truck and was hoping someone could give me some insight on the swap. I have a pretty good idea but just want to make sure I’m not in for any surprises before I start.

 

i currently have 

-4L80E (pulled from complete truck, 2002 gm Sierra 1500hd with the LQ4)

-261hd (I believe?, from same truck, has autotrac like my vmax)

-all other usable parts from the 1500..cooler lines etc. Didn’t keep the stock flexplate as I sold it with the motor 

-Michigan Motorsport 4l60 to 4l80 adapter with iss plug

-hp tuners mpvi2 for doing transmission segment swap on my current ecm (will go over power enrichment and torque management at the same time )

 

i feel like this should have me well on my way.. I know I will also have to :

shorten my driveshaft (not sure how much but would like to use the 1500hd transfer case. I’ve heard it’s shortened by 1.5” if using stock case.)

move my trans mount back appx 2.5”

And does anyone know if I need a flex plate spacer and the bolts for my setup?

any other relevant info would be great thanks guys n gals!